Method of manufacturing surface element, and surface element

ABSTRACT

The invention relates to a method of manufacturing a surface element from a thin metal sheet, and a similar surface element. In the invention, the surface of a thin metal sheet is covered by one or more substantially parallel reinforcing elements, and a thermoplastic surface layer ( 1 ) is glued onto the metal sheet ( 3 ) and the surface elements ( 2 ).

[0001] This application is a Continuation of International ApplicationPCT/FI02/00589 filed on 1.7.2002, which designated the U.S and waspublished under PCT Article 21(2) in English.

[0002] The invention relates to a method of manufacturing a surfaceelement from a thin metal sheet.

[0003] The invention further relates to a surface element formed of athin metal sheet.

[0004] Surface elements made of thin metal sheets are used for variouspurposes to form a facing e.g. in buildings, in ships and othervehicles. Such a surface element is typically manufactured by bending ametal sheet into a predetermined shape and by coating it thereafter withsuitable paint. A problem in the manufacture of such elements is thatthe thickness of the metal sheet affects the rigidity and behaviour ofthe element, as well as the acoustics. Particularly when the elementsshould be made larger, with the present technique it is necessary toincrease the thickness of the metal sheet to obtain sufficient rigidityand other properties.

[0005] An objective of the invention is to provide a method ofmanufacturing a surface element, and a surface element, which enable theuse of a thinner metal sheet than previously, while providing an elementwith better properties than in the prior art arrangements.

[0006] The method according to the invention is characterized in thatthe surface of the metal sheet is covered by at least one substantiallyparallel reinforcing element, and a thermoplastic surface layer forminga facing is glued onto the metal sheet and the reinforcing elements bypressing the plastic layer against the metal sheet and the reinforcingelements and by heating the surface layer during the gluing so that itconforms substantially to the outer surface formed by the metal sheetand the reinforcing elements and fastens the metal sheet and thereinforcing elements together, thus forming the surface element withthem.

[0007] Further, the surface element according to the invention ischaracterized in that on the surface of the metal sheet there is atleast one reinforcing element substantially parallel with the surface,and a thermoplastic surface layer is glued onto the surface of the metalsheet and the reinforcing elements, the plastic layer being pressedsubstantially against the outer surface formed by the metal sheet andthe reinforcing elements so that it fastens the metal sheet and thereinforcing elements together, thus forming the surface element withthem.

[0008] According to a basic idea of the invention, on the outer surfaceof a thin metal sheet there are one or more reinforcing elements,whereafter a thermoplastic surface layer, such as a plastic film orplastic sheet, is glued to the outer surface formed by the metal sheetand the reinforcing elements, the plastic layer being heated duringgluing and pressed against the outer surface of the metal sheet and thereinforcing elements such that it conforms thereto, thus affixing thereinforcing elements and the metal sheet together and forming a surfaceelement with them.

[0009] According to a preferred embodiment of the invention, reinforcingelements are made of incombustible material, such as profiles formed ofa thin metal sheet, wherefore such a surface element can also be used inplaces that require a high standard of fire safety, e.g. in publicpremises and in vehicles, such as ships. According to another preferredembodiment of the invention, the reinforcing elements are made of MDF,such as MDF sheets, through machining.

[0010] The invention will be described in more detail in theaccompanying drawings, in which

[0011]FIG. 1 shows schematically a surface element according to theinvention,

[0012]FIG. 2 shows schematically a cross-sectional view of a part of thesurface element according to FIG. 1 taken along the line A-A,

[0013]FIG. 3 shows schematically an advantageous cross-section of areinforcing element,

[0014]FIGS. 4a and 0.4 b show schematically examples of perforated metalsheets applicable for manufacturing a surface element, and

[0015]FIG. 5 shows an embodiment of a surface element according to theinvention viewed from the side of the facing.

[0016]FIG. 1 shows schematically a surface element 1 according to theinvention viewed from the side of the facing. Below the plastic surfacelayer provided on the surface of the element and shown in FIG. 2, theelement comprises reinforcing profiles denoted by arrows 2 in FIG. 1,the profiles forming a pattern on the surface of the surface element 1.Depending on the shape of the reinforcing elements 2 and on the locationthereof with respect to one another, various patterns can be formed onthe surface of the surface element. The patterns can be selected invarious ways depending on the required level of reinforcement and thedesired appearance.

[0017]FIG. 2 shows schematically a partial cross-section of the surfaceelement according to FIG. 1. As shown in the figure, the frame of thesurface element consists of a metal sheet 3 bent e.g. into the same formas in the figure. The shape can vary depending on the type of fastenersused to affix the surface element to the base, and it may comprisevarious projections, shoulders, openings etc.

[0018] On top of the metal sheet 3 there are reinforcing elements 2,which are shaped e.g. like crescents by way of an example, but thecross-section thereof can vary within the limits set by the desiredeffect and rigidity. The reinforcing elements 2 and the metal sheet 3are covered by a plastic surface layer 4 which constitutes the facingand is attached by gluing to the metal sheet 3 and the reinforcingelements 2 by heating the surface layer 4 and pressing it against thesurface of the metal sheet 3 and the reinforcing elements 2, so thatcertain parts of the surface element stretch as a result of the heat,thus conforming to the shapes of the surfaces.

[0019] The plastic surface layer 4 can be glued in various ways. It canbe pressed against the surface of the metal sheet and the reinforcingelements by means of a pressure difference that can be generated eitherby rapidly sucking air from the other side of the metal sheet or byproviding a higher pressure than the atmospheric pressure on the surfacefacing the surface layer. Naturally, a combination of these methods canalso be used. Furthermore, the surface layer 4 can be pressed in placeby means of a separate press element, which mechanically presses thesurface layer against the metal sheet 3 and the reinforcing element 2until the layer has assumed a desired shape. In all cases, the surfacelayer must naturally be heated in connection with the gluing to make itconform to the surface so that the film is able to adhere thereto. Theplastic surface layer can be e.g. a PVC sheet or some other suitableplastic film with appropriate heat-dependent plasticity properties, andsuitable durability and appearance for the intended purpose.Correspondingly, the plastic surface layer can be formed e.g. of a thinplastic sheet, such as an acryl sheet or the like. The gluing can becarried out by means of heat-activated or compression-activated adhesiveor e.g. moisture-activated urethane adhesive, depending on the requiredproperties and conditions of use.

[0020]FIG. 3 shows schematically a preferred embodiment of a reinforcingprofile formed by bending a very thin metal sheet into a profile thatconstitutes a reinforcing element. The reinforcing element is thus firmyet light and incombustible. Such profiles can be manufactured withvarious cross-sections, and a simple example thereof is shown in FIG. 3.A reinforcing profile can be manufactured not only by bending but alsothough extrusion or in some other manner known per se.

[0021]FIGS. 4a and 4 b show schematically two alternatives of aperforated metal sheet, which can be used to manufacture a surfaceelement according to the invention. FIG. 4a shows a metal sheetperforated with substantially evenly spaced small holes 5, through whichair is able to flow between the plastic film and the metal sheet. FIG.4b in turn shows an embodiment where broken lines denote locations 2 aof the reinforcing elements, and a few holes 5 which can be located indifferent manners, but which are placed in this case near thereinforcing element. The number and size of the holes can varyconsiderably, as long as the metal sheet is provided with holes, ifrequired, through which air can be discharged from between the plasticsurface layer 4 and the metal sheet 3 while the surface layer is beingpressed to the metal sheet.

[0022]FIG. 5 shows schematically yet another embodiment of a surfaceelement according to the invention. In this embodiment, the reinforcingelement 2′ consists of a netlike structure shown in the figure as a gridby way of an example. The operation of such a netlike structure as areinforcing element is similar to other reinforcing elements, and itadheres to the metal sheet by means of a plastic surface layer similarlyas the other reinforcing elements. When this embodiment is applied inconnection with larger surface elements, in particular, any smalldeformations occurring in a surface element as a result of thermalvariation are almost unnoticeable since there are no large and uniformreflecting surfaces in the surface elements due to such a netlikestructure. A netlike reinforcing element can consist of for examplecrosswise threads made of a suitable material, or it can be a woven netor some other net formed in a suitable manner.

[0023] In the arrangement according to the invention, the material ofthe surface element can be steel, aluminium or some other metal suitablefor the purpose. The reinforcing elements can be manufactured e.g. fromwood, various rigid materials made of fibres, such as MDF sheets, orplastic or metal, depending on the intended use and the fire safetyregulations in the destination. With respect to the prior artarrangements, the invention enables the use of a metal sheet that is upto 50% thinner for the manufacture of a surface element, while providingsurface elements with better properties, however. The most advantageousmethod is to preform metal sheets into a desired shape of the surfaceelements before the reinforcing elements and the surface layer areattached thereto. In principle, a surface element can also be a straightsheet if it is attached to a suitable place either by means of profilesor some other suitable fasteners, such as screws. What is essential isthat the surface of the metal sheet is provided with reinforcingelements, and that a thermoplastic surface layer is attached onto thesurface of both the metal sheet and the reinforcing elements to affixthe sheet and the elements together, thus forming a surface element withthem. The reinforcing elements can be placed on the surface of the metalsheet without any substantial fastening, since the plastic surface layeraffixes them firmly to the metal sheet. However, if required, thereinforcing elements can be fastened during the coating e.g.mechanically or by means of gluing only to such a degree that they stayimmobile while the surface layer is being fastened.

[0024] Furthermore, if a surface element should be perforated foracoustic or other reasons, so that an acoustic sheet which attenuatessound can be placed behind it, the coating element can be easilyperforated in a desired manner after gluing of the surface layer, or ifthe surface element is already provided with holes of a suitable shape,the surface layer can be removed from the holes afterwards.

1. A method of manufacturing a surface element from a thin metal sheetin which method at least one reinforcing element is placed on thesurface of the metal sheet substantially parallel with the surface ofthe sheet, characterized in that, a thermoplastic surface layer coveringthe metal sheet and the reinforcing elements is glued onto the metalsheet and the reinforcing elements by pressing the thermoplastic surfacelayer against the metal sheet and the reinforcing elements so that thethermoplastic surface layer fastens the metal sheet and the reinforcingelements together thus forming the surface element with them and thethermoplastic surface layer is heated during the gluing so that itconforms substantially to the outer surface formed by the metal sheetand the reinforcing elements and forms a facing on the surface element.2. A method according to claim 1, characterized in that the reinforcingelements are made of incombustible material.
 3. A method according toclaim 2, characterized in that the reinforcing elements are profilesformed of a thin metal sheet.
 4. A method according to claim 1,characterized in that the reinforcing elements are made of MDF.
 5. Amethod according to any one of the preceding claims, characterized inthat the metal sheet is perforated before coating with a plastic surfacelayer.
 6. A method according to claim 5, characterized in that the metalsheet used to manufacture a surface element is substantially evenlyperforated.
 7. A method according to any one of the preceding claims,characterized in that a surface element is manufactured by first bendinga metal sheet into a predetermined shape and by fastening reinforcingprofiles and a plastic film to the surface of the metal sheet bent intoa predetermined shape.
 8. A surface element formed of a thin metal sheetwhereby on the surface of the metal sheet there is at least onereinforcing element substantially parallel with the surface,characterized in that a thermoplastic surface layer covering the metalsheet and the reinforcing elements is glued onto the surface of themetal sheet and the reinforcing elements so that it fastens the metalsheet and the reinforcing elements together, thus forming the surfaceelement with them, the thermoplastic surface layer being heated andpressed substantially against the outer surface formed by the metalsheet and the reinforcing elements during the gluing so that it conformssubstantially to the outer surface formed by the metal sheet and thereinforcing elements and forms a facing on the surface element.
 9. Asurface element according to claim 8, characterized in that thereinforcing elements are made of incombustible material.
 10. A surfaceelement according to claim 9, characterized in that the reinforcingelements are profiles formed of a thin metal sheet.
 11. A surfaceelement according to claim 8, characterized in that the reinforcingelements are made of MDF.
 12. A surface element according to any one ofclaims 8 to 11, characterized in that the metal sheet is perforated. 13.A surface element according to claim 12, characterized in that the metalsheet is substantially evenly perforated.
 14. A surface elementaccording to any one of claims 8 to 13, characterized in that the metalsheet is first bent into a predetermined shape, and the reinforcingelements and the plastic film are attached to the surface of the metalsheet only thereafter.